Adjustable pliers

Abstract

An adjustable pliers having first and second elongated members, each elongated member comprising a handle, a jaw, and a intermediate portion between the jaw and the handle. The intermediate portion of one of the elongated members includes an elongated slot, while the intermediate portion of the other elongated member includes a pivot pin that is slidingly captured in the elongated slot. A spring is captured in the elongated slot and engages the pivot pin so as to bias the jaw of one of the elongated members toward the jaw of the other elongated member. One of the handle members also includes a stop pin in its intermediate portion that abuts the intermediate portion of the other elongated member to limit the degree to which the elongated members can pivot with respect to each other about the pivot pin.

1. An self-adjusting pliers comprising;
 first and second elongated members, each elongated member comprising a handle, a jaw with a gripping surface, and an intermediate portion between the handle and the jaw; 
 the intermediate portion of the first elongated member including an elongated slot having a first end adjacent the jaw associated with the first member and a second end spaced from the first end; 
 the intermediate portion of a second elongated member including a pivot pin that is slidingly captured in the elongated slot, the first elongated member being pivotable about the pivot pin to permit the jaws to be selectively opened or closed about a work piece and being slidable along the elongated slot to adjust the spacing between the jaws; 
 the second elongated member including a stop pin in its intermediate portion that is adapted to abut the intermediate portion of the first elongated member and the intermediate portion of the first elongated member including a series of notches external to the elongated slot so that the stop pin of the second elongated member nests in a notch when it abuts the intermediate portion of the first elongated member to maintain the relative spacing of the jaws and to limit the degree to which the second elongated member can pivot about the pivot pin; and 
 a single spring captured in the elongated slot between the pivot pin and the second end of the slot and engaging the pivot pin so as to bias the jaw of the second elongated member toward the jaw of the first elongated member, 
 whereby when the jaws are closed to grip a workpiece, the second elongated member moves toward the second end of the slot against the force of the spring to the extent necessary to accommodate the workpiece with the gripping surfaces of the jaws being substantially parallel. 
 
   
   
     2. The adjustable pliers of  claim 1  further comprising a spring retainer located in the elongated slot of the first elongated member. 
   
   
     3. The adjustable pliers of  claim 2  wherein the spring comprises a coil spring and the spring retainer comprises a post over which the coil spring nests. 
   
   
     4. The adjustable pliers in  claim 1  wherein the first and second elongated members each comprises a plurality of plates that are secured together. 
   
   
     5. The adjustable pliers in  claim 4  wherein the plates are secured together by rivets.